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Carbon Dioxide Emissions From Switchgrass And Cottonwood Grown As Bioenergy Crops In The Lower Mississippi Alluvial Valley, Michele Lea Helton

Graduate Theses and Dissertations

Marginal land of the Lower Mississippi Alluvial Valley (LMAV) has the potential to be utilized for the production of bioenergy feedstocks. Soil respiration is the gaseous emission of carbon dioxide (CO₂) from microbes and plant roots in the soil, and these emissions play an important role in the global cycling of carbon. Soil respiration can act as a positive feedback affecting climate change, and has been shown to vary depending on soil moisture, temperature, and vegetation. The objectives of this study where to evaluate the effects of land use [switchgrass (Panicum virgatum), cottonwood (Populus deltoides …

Applications Of A New Geodata Crawler For Landscape Ecology: From Mapping Natural Stream Hydrology To Monitoring Endangered Beetles, Douglas Ryan Leasure

Graduate Theses and Dissertations

An investigation of endangered American burying beetle (Nicrophorus americanus) ecology led to development of a Geodata Crawler with applications in eco-hydrology. Geodata Crawler includes a national GIS (geospatial information systems) database with layers that quantify climate, land cover, soils, human development, and other attributes of the biosphere. For user-locations in the continental United States, Geodata Crawler can rapidly tabulate site-specific statistics within automatically delineated sample areas: points, site radii, watersheds, and riparian zones, among others. Geodata Crawler supported a multi-scale analysis of N. americanus habitat at a military installation in western Arkansas to produce a Landsat-based monitoring tool. Royle's N-mixture …

Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs

Graduate Theses and Dissertations

Switchgrass (Panicum virgatum L.) has been identified as a model bioenergy feedstock crop and is expected to become an important feedstock for future renewable fuel generation. Agronomic management combinations that maximize monoculture switchgrass yield are generally well understood; however, little is known about corresponding effects of differing switchgrass management combinations on near-surface soil properties. The objective of this research was to determine the residual near-surface soil property effects of three years (2008 to 2011) of consistent management combinations to maximize switchgrass biomass production, including cultivar (‘Alamo’ and ‘Cave-in-Rock’), harvest frequency (1-cut and 2-cut systems per year), fertilizer source (poultry …

Alkaline Hydrolyzable-Nitrogen, Seeding Date, And Clay-Fixed Ammonium As Potential Indicators Of Rice Response To Nitrogen Fertilization In Arkansas, Anthony Michael Fulford

Graduate Theses and Dissertations

Several potential indicators of rice (Oryza sativa L.) response to nitrogen (N) fertilization include the soils alkaline hydrolyzableN (AHN) concentration, seeding date, and the soils clayfixed NH₄N content. Three studies were conducted to: (1) correlate AHN, determined using Illinois Soil Nitrogen Test (ISNT) or Nitrogen Soil Test for Rice (NSTaR), to plant parameters of interest and develop a fertilizer N rate calibration curve capable of predicting the 95% relative grain yield (RGY) fertilizer N rate for rice grown on clayey soils; (2) evaluate the influence of seeding date and N fertilization on rice plant growth and grain …

Increased Effluent Dosage Effects On Septic System Absorption-Field Products Of Differing Architecture Types, Andrew Richard Gibbons

Graduate Theses and Dissertations

Nationwide, approximately 20% of all homes use an on-site septic system as a form of household wastewater treatment. Since karst features are prevalent throughout the Ozark Highlands region of Northwest Arkansas, surface and groundwater resources are susceptible to contamination. Therefore, the objectives of this study were to evaluate the effects of soil condition (i.e., wet and dry) and absorption-field-product architecture type [i.e., chamber, gravel-less-pipe (GLP), polystyrene-aggregate (PSA), and pipe-and-aggregate (PA)] on in-product solution storage and biomat thickness in a profile-limited soil, and to identify the long-term acceptance rate (LTAR) of each product. During Phase I of this study (i.e., March …

Are Concentration-Discharge Relations Influenced By Water Sample Collection Methods?, William M. Welch

Graduate Theses and Dissertations

Two primary methods of stream water sampling, the U.S. Geologic Survey (USGS) equal-width increment (EWI) and point samples (PS) from vertical centroid of flow (VCF) were compared at three river sites, the White River near Fayetteville, Richland Creek at Goshen, and War Eagle Creek near Hindsville. A little over three years of concentration data, which was paired with corresponding instantaneous discharge values (http://ar.water.usgs.gov/), was gathered separately at each site by the Arkansas Water Resource Center (AWRC) and the United States Geological Survey (USGS). The purpose of this study was to evaluate how concentration is related to discharge when water samples …

Spring Thaw Ionic Pulses Boost Nutrient Availability And Microbial Growth In Entombed Antarctic Dry Valley Cryoconite Holes, Jon Telling, Alexandre M. Anesio, Martyn Tranter, Andrew G. Fountain, Thomas H. Nylen, Jon Hawkings, Virendra B. Singh, Preeti Kaur, Michaela Musilova, Jemma L. Wadham

Geology Faculty Publications and Presentations

The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of spring thaw toward fully melted holes. The cryoconite holes had a mean isolation age from the glacial drainage system of 3.4 years, with an increasing mass of aqueous nutrients (dissolved organic carbon, total nitrogen, total phosphorus) with longer isolation age. During …

Hydrogeology Of Pumice-Hosted Fens In The Winema-Fremont National Forest, Oregon, Usa, Michael L. Cummings, Jonathan Michael Weatherford, Leslie A. Mowbray

Geology Faculty Publications and Presentations

Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim study area, erosion by ephemeral streams shortly after the eruption disrupted the lateral continuity of the 270 to 300 cm-thick pumice deposit. Co-evolution of the surface- and ground-water systems in a low-relief, low-slope landscape allowed diffuse groundwater discharge from the banks of the evolving stream system. Accumulation of organic material from groundwater dependent ecosystems at these sites of discharge allowed peat deposits to form on gently sloping erosion surfaces cut …

Transformation Of Uranium In A Geological Environment, Derrell Hood

All Theses

Incorporation of uranium into iron oxide minerals is a promising mechanism for the environmental immobilization of U(VI). In this study, synthesized hematite was doped with uranium and analyzed with SEM-EDS, TEM, XRD, and ICP-MS. The results of this analysis strongly indicate uranium incorporation into the mineral, as well as the possible presence of a co-precipitated uranium mineral clarkeite. Preliminary results also shows an increase in the amount of uranium associated with the hematite particles as a function of mineral aging. Cyclic Voltammetry (CV) was used to induce and characterize electrochemical changes of uranium in the doped hematite system; these changes …

Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes

All Dissertations

The environmental fate of actinides is greatly influenced by interfacial reactions, including sorption onto solid surfaces. Because changes in the primary hydration sphere of the actinide are expected to greatly influence the thermodynamics (i.e., reaction enthalpy and entropy) of these reactions, examining actinide sorption thermodynamics may provide insight into actinide sorption mechanisms. Additionally, examining actinide sorption thermodynamics may enhance the ability to model or predict these reactions in environmental or engineered systems where variable or elevated temperatures are expected. However, few researchers have studied actinide sorption thermodynamics. Therefore, this research examined the thermodynamics of Eu(III) (a trivalent actinide analog), Th(IV), …

Short-Term Effects Of Poultry Litter Or Woodchip Biochar Amendment In A Temperate Zone Agronomic System, Katy Elizabeth Brantley

Graduate Theses and Dissertations

Biochar, a charcoal product produced by the anaerobic thermal decomposition of biomass, can provide agronomic benefits when soil applied. However, research is lacking in temperate region soils investigating specific biochar products and their effects on agronomically important crops. A greenhouse study utilizing poultry litter biochar and a field study utilizing pine woodchip biochar were conducted to observe the effects of biochar application to Northwest Arkansas soils on corn growth and nutrient availability. A third experiment investigated poultry litter and pine woodchip biochar influences on soil water retention. In all three experiments, biochar was applied at three rates (0, 5, and …

Determination Of Radon Gas And Respirable Ore Dust Concentrations In The Underground Merelani Tanzanite Mines, Evarist M. Kahuluda, Ismael N. Makundi

Tanzania Journal of Science

This study has estimated the concentrations of radon gas and respirable ore dust in the Merelani underground tanzanite mines. Two different portable monitors were used to measure the radon gas and respirable ore dust concentrations, respectively. The mean radon gas concentrations (disintegrations per second per cubic meter) ranged from 40.1 Bq/m3 to 4.2 x 103 Bq/m3 with the geometric mean of 118.4 Bq/m3 which is below the ICRP workplace guidance level of 500 - 1500 Bq/m3. The estimated mean annual effective dose (D) was 1.6 mSv which is significantly lower than the external exposure annual effective dose of 20 mSv …

Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha

Tanzania Journal of Science

This study analyzed variability in body shapes among the small Barbus species of the family Cyprinidae currently occurring in the Malagarasi and Pangani River basins years after uplift of the east African topology. Fish specimens were collected from Songati, Muumbara and Nyamagoma within the Malagarasi River basin; Hale and Pangani fall located on Pangani River. It was found that although the landmarks were placed at the same anatomical regions, significant body shapes variations existed. The relative warps analysis for Barbus trimaculatus and Barbus jacksonii populations from Malagarasi and Pangani wetlands revealed intra-locality variations as for populations from other African countries. …

Linking Land Use And Water Quality Changes In Lake Maumelle Through Benthic Sediment, Dawn Marie Johnson

Theses and Dissertations

Lake Maumelle is a reservoir in Pulaski County, Arkansas that was finished in 1958 for the purpose of supplying potable water to Little Rock and surrounding areas. It is an oligotrophic, monomictic lake with a generously forested watershed. There has been an increase of urbanization in the watershed which may influence the water quality. This research examines the reservoir's sensitivity to land use/land cover change for the lake by analyzing the benthic sediment. By using multidisciplinary methods, cores were examined using mass accumulation rates, grain size analysis, elemental analysis, phase identification, and diatom identification. Those results were then compared to …

Hairy Stalagmites, A New Biogenic Root Speleothem From Botswana, Gerhard C. Du Preez, Paolo Forti, Gerhard Jacobs, Anine Jordaan, Louwrens Tiedt

International Journal of Speleology

Ngamiland in northwestern Botswana hosts the Gcwihaba Caves which present unique subterranean environments and host speleothems never before recorded. Cave atmospheric conditions can be extreme with temperatures as high as 28°C and relative humidity nearing 99.9%. Within Dimapo and Diviner’s Caves peculiar root speleothems that we named ‘Hairy Stalagmites’ were found. These stalagmites are closely associated with the roots of Namaqua fig (Ficus cordata) trees that enter the cave environment in search of water. Pieces of broken stalagmites were sampled from Dimapo Cave for further investigations. Stereo and electron microscopy revealed that the Hairy Stalagmites consist of multiple …

Warm Water Benthic Foraminifera Document The Pennsylvanian-Permian Warming And Cooling Events – The Record From The Western Pangea Tropical Shelves, Vladimir Davydov

Geosciences Faculty Publications and Presentations

Shallow warm water benthic foraminifera (SWWBF), including all larger fusulinids (symbiont-bearing benthic foraminifera), are among the best indicators of paleoclimate and paleogeography in the Carboniferous and Permian. The distribution of benthic foraminifera in space and time constrain important tectonic, paleogeographic and climatic events at a global scale. The North American shelves during Pennsylvanian and Permian time - though geographically within the tropical belt - are characterized by temperate environments with significantly lower foraminifera diversification and rare occurrences of warm water Tethyan forms, that are in general appear in the region as a migration entities. Such environments allow documentation of warming …

Investigations Of Potential Microbial Methanogenic And Carbon Monoxide Utilization Pathways In Ultra-Basic Reducing Springs Associated With Present-Day Continental Serpentinization: The Tablelands, Nl, Can, P. L. Morrill, W. J. Brazelton, L. Kohl, A. Rietze, S. M. Miles, H. Kavanagh, M. O. Schrenk, S. E. Ziegler, Susan Q. Lang

Faculty Publications

Ultra-basic reducing springs at continental sites of serpentinization act as portals into the biogeochemistry of a subsurface environment with H2 and CH4 present. Very little, however, is known about the carbon substrate utilization, energy sources, and metabolic pathways of the microorganisms that live in this ultra-basic environment. The potential for microbial methanogenesis with bicarbonate, formate, acetate, and propionate precursors and carbon monoxide (CO) utilization pathways were tested in laboratory experiments by adding substrates to water and sediment from the Tablelands, NL, CAD, a site of present-day continental serpentinization. Microbial methanogenesis was not observed after bicarbonate, formate, acetate, or propionate addition. …

Short- And Long-Term Trends In Ecological Interactions: From Predator-Prey Interactions To Phanerozoic Diversification, Subhronil Mondal

USF Tampa Graduate Theses and Dissertations

During the last two decades, a broad spectrum of short- and long-term studies on different taxonomic groups has enriched our understanding about how dynamics of taxonomic and ecological diversification have changed through geologic time. There are two major issues that have impacted these studies: the quality and quantity of data used are often insufficient in various ways and the methods used may produce results that are more equivocal than supposed. To investigate these issues more fully, this dissertation focuses on studies on two major aspects: 1) short-term studies examining the nature of successful and unsuccessful predatory attacks on Plio-Pleistocene bivalves; …

Peptide Arrays For Detecting Naphthenic Acids In Oil Sands Process Affected Water, Kamaljit Kaur, Subir Bhattacharjee, Rajesh G. Pillai, Sahar Ahmed, Sarfuddin Azmi

Pharmacy Faculty Articles and Research

Naphthenic acids (NAs) are water-soluble components of petroleum. The characterization and quantification of NAs by analytical methods have proved quite challenging, whilst the toxic effects of these water-soluble compounds on a variety of organisms adversely affecting reproduction and steroid production is becoming apparent. In this study, we report a fluorescence-based competitive binding method for rapid sensing of the presence of NAs using cellulosic peptide array strips as sensors. The peptide array was designed from sequences derived from the estrogen receptor (ER). Several of these peptides were able to detect the presence of NAs at low micromolar (∼5 mg L^{−1 …}

Utilizing Indicator Of Reduction In Soils Tubes To Affirm A Serpentinitic Hydric Soil On The California Central Coast, Jason Demoss

Natural Resources Management and Environmental Sciences

Wetlands are vital ecosystems that are crucial in maintaining the life of rare and unique soils, plants, and animals. These ecosystems are key players in water storage, water filtration, carbon storage, and harboring unique species. Since the intervention of human development on the Earth’s surface, almost 50% of the Earth’s original wetlands have either been damaged or destroyed. The identification and assessment of both new and old wetlands is crucial in the survival of these precious ecosystems and their conservation. A 3 month-long study was performed to confirm the hydric status of a soil derived from serpentinitic parent material. The …

Goomig Farmlands Development Baseline Water Quality In The Lower Keep River, D L. Bennett, Richard J. George Dr

Resource management technical reports

In 2008 the Ord Irrigation Expansion Project was approved by the Western Australian Government to develop irrigated agriculture on the Weaber Plain. By mid-2014 construction of almost all of the water supply, drainage, access, monitoring and other infrastructure for the 7400ha Goomig Farmlands development had substantially been completed. An important concern is the effect the Goomig Farmlands development may have on the water quality of the downstream lower Keep River aquatic environment, particularly as it relates to threatened species that inhabit or may inhabit the area. Possible increases in salinity, nutrients, suspended sediment, heavy metals and farm chemicals delivered in …

Aptian To Santonian Foraminiferal Biostratigraphy And Paleoenvironmental Change In The Sverdrup Basin As Revealed At Glacier Fiord, Axel Heiberg Island, Canadian Arctic Archipelago, Claudia J. Schröder-Adams, Jens O. Herrle, Ashton F. Embry, James W. Haggart, Jennifer M. Galloway, Adam T. Pugh, David M. Harwood

ANDRILL Research and Publications

Exceptional exposures of a High Arctic Cretaceous sedimentary record were studied at Glacier Fiord, Axel Heiberg Island. The succession reveals a complex Aptian to Santonian paleoenvironmental history of the Sverdrup Basin that documents several global events. Foraminiferal faunas in combination with rare macrofossil occurrences permit the distinction of nine zones that facilitate biostratigraphic correlations to other High Arctic locales, the Beaufort Mackenzie Basin and the Western Interior Sea. The depositional environment as exposed in the Christopher, Hassel, Bastion Ridge and Kanguk formations changed frequently from a shelf to a shoreface setting. Most sequence boundaries appear to be conformable where shoaling …

A New Type Of Jarosite Deposit On Mars: Evidence For Past Glaciation In Valles Marineris?, Selby Hearth

Geology Faculty Research and Scholarship

No abstract provided.

Discovery Of A 240 Million Year Old Nematode Parasite Egg In A Cynodont Coprolite Sheds Light On The Early Origin Of Pinworms In Vertebrates, Jean-Pierre Hugot, Scott Gardner, Victor Borba, Priscilla Araujo, Daniela Leles, Átila Da-Rosa, Juliana Dutra, Luis Fernando Ferreira, Adauto Araújo

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Background: We report the discovery of a nematode parasite egg (Nemata: Oxyurida) from a coprolite closely associated with the remains of several species of Cynodontia, dated to 240 million years old. This finding is particularly significant because this is the oldest record of an oxyurid nematode yet discovered, and because the cynodonts are considered a stem-group of the mammals.

Methods: We extracted material from a fully mineralized coprolite by both scraping the surface, and removing fragments from its interior with clean dental instruments used a single time. A single drop of glycerol from a new vial was added as a …

2014 Future Earth Young Scientists Conference On Integrated Science And Knowledge Co-Production For Ecosystems And Human Well-Being, Ivy Shiue, Et. Al.

Research Collection Yong Pung How School Of Law

Effective integration in science and knowledge co-production is a challenge that crosses research boundaries, climate regions, languages and cultures. Early career scientists are crucial in the identification of, and engagement with, obstacles and opportunities in the development of innovative solutions to complex and interconnected problems. On 25–31 May 2014, International Council for Science and International Social Science Council, in collaboration with the International Network of Next-Generation Ecologists and Institute for New Economic Thinking: Young Scholars Initiative, assembled a group of early career researchers with diverse backgrounds and research perspectives to reflect on and debate relevant issues around ecosystems and human …

Redox Chemistry In The Phosphorus Biogeochemical Cycle, Matthew A. Pasek, Jacqueline M. Sampson, Zachary Atlas

School of Geosciences Faculty and Staff Publications

The element phosphorus (P) controls growth in many ecosystems as the limiting nutrient, where it is broadly considered to reside as pentavalent P in phosphate minerals and organic esters. Exceptions to pentavalent P include phosphine—PH₃—a trace atmospheric gas, and phosphite and hypophosphite, P anions that have been detected recently in lightning strikes, eutrophic lakes, geothermal springs, and termite hindguts. Reduced oxidation state P compounds include the phosphonates, characterized by C−P bonds, which bear up to 25% of total organic dissolved phosphorus. Reduced P compounds have been considered to be rare; however, the microbial ability to use reduced P …

Eocene-Oligocene Latitudinal Climate Gradients In North America Inferred From Stable Isotope Ratios In Perissodactyl Tooth Enamel, Alessandro Zanazzi, Emily Judd, Andrew Fletcher, Harold Bryant, Matthew J. Kohn

Geosciences Faculty Publications and Presentations

The Eocene-Oligocene transition (~ 34 Ma) was one of the most pronounced episodes of climate change of the Cenozoic. In order to investigate this episode of global climate cooling in North America, we analyzed the carbon and oxygen stable isotope composition of the carbonate component of 19 perissodactyl (horse and rhino) tooth enamel samples from the Eocene-Oligocene rocks of the Cypress Hills Formation (southwestern Saskatchewan, Canada); we then compared the results with previously published data from the US Great Plains (Nebraska, South Dakota, and Wyoming).

Average (± 1σ) perissodactyl enamel δ¹³C values (vs. V-PDB) in the Eocene (-8.8 …

Groundwater Controls On Physical And Chemical Processes In Streamside Wetlands And Headwater Streams In The Kenai Peninsula, Alaska, Michael Kroh Callahan

USF Tampa Graduate Theses and Dissertations

For this dissertation I studied groundwater and surface water interactions in the Kenai Lowlands, Alaska. In particular, I examine two important aspects of groundwater and surface water interactions: 1) Groundwater's influence on surface-water temperature; and 2) Groundwater's role in forming hydrologic flow paths that can connect uplands to streamside wetlands and streams. Chapter 2 investigates the controls on stream temperature in salmon-bearing headwater streams in two common hydrogeologic settings: 1) drainage-ways, which are low-gradient streams that flow through broad valleys; and 2) discharge-slopes, which are high gradient streams that flow through narrow valleys. The results from chapter 2 showed significant …

Public School Science Education And Geographically-Specific Environmental Sustainability Issues: Implications For Social Work Education, Amanda Gallion

Mahurin Honors College Capstone Experience/Thesis Projects

The focus of this project was to examine the educational practices of Kentucky-based public school teachers (grades 4th-8th) related to their efforts to incorporate sustainability into the science classroom and specifically related to the teachers’ focus or lack of focus on karst landscape. The major themes that were analyzed were how educators include this content into their classroom material and how this impacts their students in the area of environmental sustainability. The themes analyzed were: environmental sustainability as a lifestyle choice; education about environmental sustainability, the nexus of family, school, and community; the importance of geographical context in regards to …

Ecogeomorphic Feedbacks And Flood Loss Of Riparian Tree Seedlings In Meandering Channel Experiments, Li Kui, John C. Stella, Anne Lightbody, Andrew C. Wilcox

Geosciences Faculty Publications

During floods, fluvial forces interact with riparian plants to influence evolution of river morphology and floodplain plant community development. Understanding of these interactions, however, is constrained by insufficient precision and control of drivers in field settings, and insufficient realism in laboratory studies. We completed a novel set of flume experiments using woody seedlings planted on a sandbar within an outdoor meandering stream channel. We quantified effects on local sedimentation and seedling loss to scour and burial across realistic ranges of woody plant morphologies (Populus versus Tamarix species), densities (240 plants m^-2 versus 24 m^-2), and sediment …